The transmissions that are usually employed in dumpers, loaders, excavation loaders and lift trucks, and also used in vehicles operated on the road such as mobile cranes. Here are involved, as a rule, powershift transmission with front-mounted hydrodynamic torque converters where a continuous and automatic torque increase can be obtained during an increase of the working resistance of the motor vehicle such as a construction machine. Driving torques of the transmission can be produced driving torques of the transmission which correspond to about a triple value of the motor torque.
The power flow in the individual gears of a transmission of the above mentioned kind is produced by a combination of the hydraulically shiftable clutches. The clutches must be shiftable under load for the reversal in loaders, among others, and therefore, can absorb much energy. The design of the housing and the arrangement of the shafts of the transmission must be adapted to the application.
Within the scope of the Applicant's EP 0 759 129 B1 is described a multispeed reverse transmission shiftable under load having at least one input shaft, countershafts and gears which form an input gearset and shifting clutches situated on the countershafts with idle gears which can optionally be no-rotatably connected with one of the countershafts for gear and direction change. One fixed gear and idle gears in constant mesh therewith form the input gearset; in addition, one fixed gear situated on a countershaft and inconstant mesh with two idle gears form an output gear chain; the countershafts are interconnected byfixed gears and one idle gear. Another such transmission is the object of the Applicant's EP 0 796 400 B1.
The problem on which this invention is based is to outline a shiftable multispeed reverse transmission having a higher power compared to the prior art. Besides, the inventive transmission must have good efficiency and be sturdy.